Internal combustion engine with an auxiliary combustion chamber

Abstract

Disclosed is an internal combustion engine comprising a main combustion chamber, a first auxiliary combustion chamber and a second auxiliary combustion chamber. The first auxiliary combustion chamber is connected to the main combustion chamber via a first connecting passage in which the spark plug is located. The second auxiliary combustion chamber having no spark plug is connected to the main combustion chamber via a second connecting passage. A flame of the combustible mixture contained in the first connecting passage and ignited by the spark plug reaches the second connecting passage and causes the ignition of the combustible mixture in the second auxiliary combustion chamber. As a result a burning jet is injected from the second connecting passage into the main combustion chamber a little while after the burning jet is injected from the first connecting passage into the main combustion chamber.

What is claimed is: 
     
       1. An internal combustion engine comprising: a cylinder block having a cylinder bore therein;   a cylinder head on said cylinder block;   a piston reciprocally movable in said cylinder bore, said piston and said cylinder head defining a large main combustion chamber therebetwen when said piston is in its top dead center position;   an intake valve movably mounted on said cylinder head through which a combustible mixture is fed into said main combustion chamber;   an exhaust valve movably mounted on said cylinder head through which exhaust gas is discharged from said main combustion chamber;   means defining a first auxiliary combustion chamber in said cylinder head;   a first passage directly fluidly communicating said first auxiliary combustion chamber and said main combustion chamber, said first passage extending obliquely relative to the axis of said piston is a direction downward and toward one side of the main combustion chamber;   means defining a second auxiliary combustion chamber in said piston;   a single second passage in said piston directly fluidly communicating said second auxiliary combustion chamber and said main combustion chamber, said second passage opening into said main combustion chamber at a position near the position at which the first passage opens into said main combustion chamber, said second passage also extending obliquely to the axis of the piston in a direction upward and toward a side of the main combustion chamber opposite said one side and having an axis substantially parallel to the axis of the first passage; and   a spark plug having a spark gap in one of said first passage and said first auxiliary combustion chamber, said second passage and said second auxiliary combustion chamber not having a spark gap of a spark plug therein.   
     
     
       2. An internal combustion engine as claimed in claim 1, wherein said first auxiliary combustion chamber is connected only to said main combustion chamber, the spark gap of said spark plug being located in said first connecting passage. 
     
     
       3. An internal combustion engine as claimed in claim 2, wherein said combustible mixture is a lean air-fuel mixture. 
     
     
       4. An internal combustion engine as claimed in claim 2, wherein said combustible mixture is an air-fuel mixture containing the recirculated exhaust gas therein. 
     
     
       5. An internal combustion engine as claimed in claim 1, wherein the axis of said first connecting passage and the axis of said second connecting passage are common to each other. 
     
     
       6. An internal combustion engine as claimed in claim 1, wherein: one end of said second passage which opens directly into said main combustion is substantially centrally disposed on the top of said piston.